The Crab NebulaΓÇÖs filamentary structure is the part of the original explosion cloud that is expanding into interstellar space. Interstellar space is not truly empty but contains clouds of invisible gas and dust, which vary in density from region to region and which offer differing degrees of resistance to the nebulaΓÇÖs exploding cloud, causing it to pile up irregularly into filaments. The resistance also causes the matter in the filaments to heat and emit colored light.
The white light from the nebulaΓÇÖs diffuse inner region has provided clues to one of the most peculiar objects known to astronomers: the Crab Pulsar. Astronomers discovered that the Crab NebulaΓÇÖs white lightΓÇöunlike that of ordinary nebulaeΓÇöwas
